1. Field of the Invention
The present invention relates generally to a crop harvesting machine and, more particularly, is concerned with drive means for operating the header and conditioner rolls of the machine.
2. Description of the Prior Art
Prior art crop harvesting machines have a mobile frame and a crop harvesting header suspended on the frame for vertical movement relative thereto. One prior art machine, such as disclosed and illustrated in U.S. Pat. No. 3,820,311, employs a drive arrangement wherein a drive transmission housing is mounted on the side of the header from which rotary power is transmitted to drive the conditioner rolls, reel and cutterbar being mounted in the header.
The drive housing includes a drive output sheave located adjacent an inner side of the header from which rotary motion is transmitted to the cutterbar drive mechanism and a pair of drive output shafts being aligned with adjacent ends of the conditioner rolls and universally connected thereto by a pair of telescoping shafts. The drive transmission housing must be vertically adjusted to adjust the tension in an endless belt which extends between the output sheave of the housing and the input sheave of the cutterbar drive mechanism. Drive for the header reel is obtained from an opposite end of the upper conditioner roll through the provision of drive transmitting components on the opposite outer side of the header.
One disadvantage of the above-described prior art drive arrangement is that the drive transmission housing, in being mounted on the header, moves with the header as the latter follows surface undulations during field operation of the machine and thereby the angular relationship between the pto driveline and the housing is constantly changing. Other disadvantages appear to reside in the inconvenience of having to adjust the transmission housing in order to adjust belt tension, the number of gears necessary to transmit rotary driving power to the conditioner rolls, the necessity for two telescoping universal-joint type shafts for interconnecting the gears to the conditioner rolls, and the provision of the drive mechanism for the reel on the opposite side of the header where it is vulnerable to damaging contact with obstacles.